1. Field of the Invention
The present invention generally relates to telecommunications. More particularly, the present invention relates to a method of and system for the transfer of SONET communications across a packet network.
2. Related Art
Synchronous Optical NETwork (SONET) is a widely used standard for the transport of telecommunications traffic. SONET defines an optical based transmission hierarchy involving multiple optical carrier (OC) levels carrying digital synchronous transport signals (STSs).
In the development of telecommunications and/or data networks, significant investment is required to deliver SONET service. This investment includes the acquisition of SONET products and the procurement of optical communications media to deliver bandwidth. Unfortunately, SONET products are expensive. In addition, SONET products provide few features that enable the efficient utilization of bandwidth.
In contrast, packet switched networks, such as Internet Protocol (IP) networks, include elements such as routers and ethernet switches that are geared to much wider markets are therefore available at lower costs than SONET products. Moreover, packet switched network elements provide greater flexibility in the utilization of bandwidth.
Accordingly, what is needed is a method and system that delivers the popular SONET service, but provides the cost savings and bandwidth efficiencies associated with packet switched networks.
The present invention is directed to a method of and system for transferring Synchronous Optical NETwork (SONET) traffic across a packet network. A method, according to an embodiment of the present invention, includes the steps of reading a SONET transmission, decoding the SONET transmission into a data structure, converting the data structure into packets, and sending the packets across the packet network.
In an embodiment of the present invention, the step of converting the data structure into packets includes extracting a synchronous payload envelope (SPE) from the data structure and compressing the extracted SPE, if possible.
In a further embodiment, the step of converting the data structure into packets includes determining whether the data structure represents a slot of concatenated STS-Nc service; and if so, i) extracting a concatenated synchronous payload envelope (SPE-Nc) from the data structure, ii) fragmenting the SPE-Nc into a N SPE-1 payloads, and iii) concatenating each of the N SPE-1 payloads with a header. An advantage of the present invention is the capability to efficiently utilize bandwidth in the transfer of SONET traffic across the packet network.